Home / Products / / ALF 225 Duct Leakage Tester

ALF 225 Duct Leakage Tester

The ALF 225 duct leakage tester is a portable, and totally self-contained primary device machine. It can generate up to 225l/s of airflow and test up to 2500Pa static pressure.

The ALF 225 duct leakage tester is a compact, portable and totally self-contained unit. Commissioning engineers are provided with a high-quality ALF 225 with everything needed to test duct work systems for leakage under both Positive and Negative pressure. It is capable of developing static pressures from -2500Pa to +2500Pa, and flow rates of 1 to 225l/s. This provides approximately 210l/s of air flow for Class A leakage tests and up to 130l/s for Class C/D leakage tests.

A single all in one instrument means that this duct leakage tester is not only simple to use but also removes the complexity that might be associated with operating a duct work leakage tester and other forms of testing equipment. The ALF 225 duct leakage tester is easily transportable and  is ready to use from the moment it is unpacked.

The ALF 225, like all our leakage testers, utilities three rapid change (push in – pull out) conical inlet nozzles, making this machine a primary measuring device. These precision machined nozzles, combined with a recently enhanced control POD gives an accuracy of +/-2% of reading. Test data can be saved to an SD card and can be streamed over USB connection to a computer.


There are two models of the ALF 225:
The ALF 225
The ALF+

The ALF 225 provides a closed loop PID control feature that allows you to run a closed loop controlled leakage test. The user select from the following available test standards SMACNA, EN1507 / 12237 or DW/143. Configurable test parameters include; duct size, test pressure, test duration and test class. Once configured appropriately, the ALF 225 control pod will then calculate the allowable max leakage for the test. The control pod will then run the test and pressurize or depressurize the ductwork to the set test pressure and monitor the leakage rate. Based on the performance of the ductwork, the control pod will indicate if the ductwork passed the test.

The ALF+ model offers greater accuracies with the inclusion of an ambient conditions module which will automatically measure the ambient temperature and barometric pressure for you. From these measurements, the real time air density will be calculated and used when calculating the leakage rate of the ductwork under test.

Both ALF models allow the user to calculate the leakage rate in either ‘Actual’ conditions, or ‘Standard’ conditions. Actual conditions will use the real time temperature and barometer (or the temperature & barometer entered by the user) to calculate the air density of the air moving through the ALF unit. Standard conditions provides the leakage rate using air density at standard conditions. i.e: 1.2 kg/m³.
Both ALF models utilize the same three conical inlet nozzles designed to ISO5801:2007 and each unit is supplied with a fully calibrated instrument.

Standards the ALF225 allows you to test to include:
EN12237 Ventilation For Buildings
EN1507 Ventilation For Buildings

Standards EN 1507 / 12237, DW/143, SMACNA
Volume Flow Measurement 1 to 225 l/s – over nozzle ranges
Pressure Measurement Range ±2500 Pa
Typical Duty Points 130 l/s at 2000 Pa, 210 l/s at 500 Pa
Pressure Measurement Accuracy ±1% of reading ±1 digit
Leakage Flow Accuracy ±2.5% of reading ±1 digit
Resolution 1 Pa
Sensor Damping 0.5s to 8s
Power 800W
Voltage 240Vac 50/60Hz (or 110Vac 50/60Hz available)
Unit Size 39W x 52D x 74H cm
Unit Weight 32kg
Carry Case (c/w Accessories) Size 45W x 45D x 55H cm

Carry Case (c/w Accessories) Weight 10.5kg
Clip on Trolley Size 38W x 20D x 94H cm
Clip on Trolley Weight 6.7kg
Maximum recommended SD Card 32 GB SDHC Class 1

– Duct leakage testing
– Chilled beam testing
– AHU testing
– End of line testing